Planar spin valves fabricated on manganite epitaxial thin films

We fabricate micrometric constrictions in manganite epitaxial thin films by atomic force microscope local anodization. We demonstrate the possibility of realizing planar spin valve devices, exhibiting hysteretic transport behavior as a function of the external magnetic field, associated with magnetic domains orientation. We also observe nonlinear current-voltage characteristics which become increasingly linear in external field and we attribute this crossover to the disappearance of energy barriers of domain walls at the constriction.